Yellowstone CountyPower Outage History
What this grade means
Top 20% most reliable nationally — infrequent, short outages. This county ranks in the most reliable fifth of all US counties in our dataset, based on 12 years of real DOE outage records: outages happen less often here, and when they do occur they tend to be resolved quickly compared to the rest of the country. Baseline outage risk is low, though a severe local storm can still occasionally cause a longer-than-usual outage regardless of the long-term track record.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Aug 6, 2024 | 32 hrs | 14,848 (19%) | Thunderstorm Wind |
| Jul 25, 2022 | 18 hrs | 7,375 (9%) | Hail |
| Apr 17, 2025 | 18 hrs | 7,083 (9%) | Winter Storm |
| Feb 7, 2024 | 7 hrs | 6,265 (8%) | Unnamed event |
| Mar 2, 2024 | 4 hrs | 6,261 (8%) | Unnamed event |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Yellowstone County, Montana that day.
Over the 6 years from 2020 to 2025, Yellowstone County recorded 308 distinct power outage events, averaging 2.7 hours per event.
The single worst outage on record in Yellowstone County started August 6, 2024 (Thunderstorm Wind), lasting 32 hours and leaving up to 14,848 customers without power (19% of the county) at its peak.
July has historically been the worst month for outages in Yellowstone County, with 47 events recorded during that month across the dataset.
Based on this history, Yellowstone County earns a Reliability Grade of A, placing it in the 89th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Montana
Counties with the closest reliability grade and national percentile to Yellowstone County.
| County | Grade | National percentile |
|---|---|---|
| Silver Bow County | A | 89th |
| Custer County | A | 87th |
| Stillwater County | A | 90th |
| Gallatin County | A | 92nd |
| Beaverhead County | A | 84th |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Yellowstone County?
Between 2020 and 2025, Yellowstone County recorded 308 outage events, averaging 2.7 hours each.
What is Yellowstone County's reliability grade?
Yellowstone County has a Reliability Grade of A, in the 89th national percentile.
What was the worst power outage in Yellowstone County?
The worst outage on record started August 6, 2024 (Thunderstorm Wind), lasting 32 hours and affecting up to 14,848 customers.